Variable leverage brake mechanism



Oct. 27, 1936. A. EQWILSHUSEN V ARIABLE LEVERAGE BRAKE MECHANISM Filed March 7, 1934 INVEN TOR.

Patented Oct. 27, 1936 he UNITED STATES PATENT OFFICE VARIABLE LEVERAGE BRAKE 'MECHANISM August E. fWilshusen; HighlandP-ark Mich. Application March 7, 1934, SeriaLNo." 714,418;

11 Claims. (01. WI-#516) My invention relates to improvements in which brake or similar operatedmechanisms are actuated by a control lever or similar members; and the objects of my improvements are, first, to .pro-

vide a,variable..leverage mechanism 'for operating a brake mechanism and which will provide an; increasingly greater leverage throughout the operative movement of the brake mechanism; second; to provide a variable leverage brake.

10 mechanism havingaplurality of pairs of toggle or-knee acting links operatively connected to-- gether and with the brake mechanism; third, to provide a variabl leverage brake mechanism in which the operating pressure is applied at a 55: point substantially onvits axis and between its ends; fifth, to provide a variable leverage brake mechanism in which the operating pressure is applied thereon .at one pointwthroughout the; movement of the brake operating mechanism; 20 and sixth, to provide a variable lever brake mech variable leveragebrake mechanism installed ona vehicle having front and rear wheel brakes; 30 Fig. 2, a: plan view of myva-riable leverage brake mechanism in its position corresponding to the beginningof its movement for operating the brakes; Fig. 3, a side view of thevariable leveragetbrakemechanism disclosed in Fig. 2; Fig. 35. 4-; a plan view of the variable leverage brake mechanism corresponding to a position in which the brakes have been operated at their applied or braking position; and Fig. 5, an alternative construction of myvariable leverage brake mech- 40 anism when installed rearwardly of a. brake contlOllEVGl.

Similar numerals refer to similar parts throughout the several views. I

The brake pedal or brake control lever l is 45 disclosed in Fig. 1 as being suitably mounted on theshaft 2,.the brake pedal I being adapted to pivotally move. about the center of the shaft 2, the brake .pedall having the extension portion 3 extending through the slot 4' in the toe board 5 of 50 thevehicle, the extension portion 3 being provided with the pedal pad 6 for receiving the foot of the operator. The brake drum! is suitably mounted to be engaged by the brake shoot, the brake shoe 8 being suitably provided with operating mecha- 5 nism for actuating the brake shoe; 8. to an engaged position relative to-the drum 1, the brake operating mechanism being suitably provided with the lever B to which is pivotally connected the rod 10, the rod Ill-being provided with a. yoke and further pivotally connected.- to the double 5 endlever ll whichis pivotally connected at its lower end tothe yoke end ;of the rod l3twhich may extend forwardly in the vehicle to operatively connect with the front wheelbrake mechanism'of the vehicle,the rod I0 being disclosed 10 as being operatively connected, as above described, to. the rear brake operating mechanism of v the vehicle. I v

The upper end of the double end lever 'I l .is pivotally connected with the yoke end of the rod M. The links or members 15 and Hi aremounted to pivotally move at their forward ends about the pin I! which extends through the bosses l8-- of the -yoke|;9,the links l5 and I6 being adapted to pivotally move adjacent one another in the jaw spaceor portion 20 of the bosses I8 on the yoke member 89, the links I 5 and I Bbeing restrained from'longitudinalmovement. i

It is to be noted that-thelyoke member 19 will be suitably anchored in any portion of the vehicle, the yoke member I 9 being disclosed inFig-- ures ,1 and4 as being anchored in the frame cross member 2 I, the yoke member!!! having a thread ed end extending through the vertical web of the frame cross member 2|, the threaded end of the yoke member! being secured by the nuts 22 and 23 and the lock washerr24, the yoke mem-- ber l9 thus being adjustably mounted relative to the frame cross member 2|. 2 a a The links l5 and "5 are pivotally connected to v the upper and lower pairs of links 25 and 26, a pair of the links 25 andL26 being located at eachouter side of the'variable leverage brake mechanism, a'pair of links 25 and 26 being-connected to the link 15 by the rivets 21, the second pair of links 25 and 26 being connected to the link IB by the rivets 28. The rear ends of the pair of links 25 and 26 will bepivotally connected to the bracket 29 by the rivets 30 and 3|. The bracket 29 will be provided with the oppositely disposed bosses or boss portions 32 which extend between each of the pairs of links 25 and 26, the rivet 3| extending through suitable holes in the pairs of links 25 and 26 and in the boss portions32 of the bracket 29. The bracket 29 is further provided with the oifsetboss portion 33 which is provided with the hole 34 through which extends the forward end of the rod M, the forward end of the rod l4 being suitably threaded so that it may be secured in the opening 34 of the boss portion 33 ISIS mounted respectively on the rivets 2'! and 28 which thus pivotally connect the links 38 and 39 with the links I5 and I6, the links 38 and. 39 being further pivotally connected together at their inner or rearmost ends by the pin 48 which extends through holes in the inner or rearward ends of the links 38 and 39 and also through the jaw por- 1O tions 41 of the yoke end 42 which is provided with the rod portion 43 which may be threaded at its outer end to connect with the yoke 44 which is pivotally connected by the pin 45 to the lever arm 48 which forms a portion of the brake pedal I and pivotally moved therewith. The rod portion 43 may be suitably bent or formed to extend below the links 29 to suitably connect with the lever arm 48, thus enabling the lever arm 46 to pivotally move below or adjacent the variable leverage brakemechanism. The brake pedal I will be suitably provided with the hub portion 41 which may extend longitudinally along the shaft 2 for a sufficient length to permit the lever arm 46 tobe w located in alignment with the yoke 42 and at the same-time permit the brake pedal I, together with its extension 3 and pad 6 to be suitably located at one side of the variable brake mechanism.

In operation, when the brake pedal I is pivotally moved downwardly by pressure being applied W to the pad 6 by the foot of the operator of the vehicle, the lever arm 46 will exert a thrust applying pressure through the yoke 44, the rod 43 and the yoke 42 to move the pin 48, together with the links 38 and 39 forwardly or to the left as viewed in Figures 1, 2, 3, and 4, the forward movement of the links 38 and 39 moving the rivets 21 and 28 forwardly and at the same time outwardly relative to the axis of the yoke member I9, the movement of the rivets 21 and 28 thus causing 40:? the links I5 and I6 to move forwardly, the links I5 and I6 pivotally moving about the pin I1, the forward ends of the links I5 and I6 being anchored in the yoke I 9 and preventing longitudinal movement of the links I5 and I6.

It will thus be noted that the above described movement of the links 38 and 39, together with the links I5 and I6 will cause a spreading movement of said links I5, I6, 38, and 39 and will thus exert a pull through the pairs of links 25 and 2B to'the bracket 29, causing the bracket 29, together with its operatively connected rod I4, to move forward with the downward movement of the brake pedal I.

It will thus be noted that my variable leverage brake mechanism is provided with a double toggle or knee action joint operatively connected so that a force may be applied therethrough tothe double togglejoint or knee action mechanism, thus tending to move or straighten the links I5, I6, 38, and 39 from their normal position as disclosed in Fig. 2 to or toward their positions as disclosed in Fig. 4, corresponding to the position of the brake mechanism, provided with the brake drum I and the brake shoe 8-, when the brake drum I and the brake shoe 8 are in their operative positions for effecting a braking movement of the vehicle.

It is to be noted that the above mentioned movement of the links I5, I6, 38, and 39 will cause an increasing pressure to be applied longitudinally through the pairs of links 25 and 26 to actuate the rod I4, together with its operatively connected mechanism, for operating the brakes of a vehicle, throughout the operative movement of the brake mechanism. I

It will thus be noted that as the pin 40 is moved forwardly by the downward movement of the pedal I, the rivets 21 and 28 will be moved forwardly at a slower rate of speed which will permit an increased pressure to be applied through the pairs of links 25 and 25 to operatively move the rod I4, an increasingly greater leverage thus being applied throughout the movement of the variable leverage brake mechanism.

It is also to be noted that the greater leverage will beapplied at or toward the end of themovement of the brake pedal I which will correspond to the effective brake operating position of the When it is desired to accommodate an installation in which the brake pedal I is located ahead of the point in which it is desired to mount my variable leverage brake mechanism, this may be accomplished as disclosed in Fig. 5, in which the bracket 48 may be suitably secured to the cross member 49 by the rivets 58, the bracket-48 being provided with a central opening 5| through which the rod 52 may extend to operatively connect by its yoke end 55, with the pin 48, the rod 52 beingfurther pivotally connected with the lever arm 46, as disclosed in Fig. 5. Y

Also it is to be noted that in Fig.5, the pairs of links 25 and 26 will occupy a convergent position relative to one'another in their normal position, the rearward ends of the pairs of links 25 and 26 being pivotally connected to the rod 53 by means of the pin 54, the rod 53 being operatively and pivotally connected with the upper end of the double lever arm I I in a similar manner to that disclosed in Fig. 1.

It is to be further noted that my variable leverage brake mechanism 'will thus be mounted to provide, when used in Fig. 1, an adjustable mounting at its forward end and also will be adjustably connected at its rearward end to the rod It is also to be noted that the increased leverage which will be applied to the mechanism for operating the brakes of the vehicle will be applied continuously from the beginning of the movement of the brake pedal I to the end of its movement, thus eliminating any interruption of the increased leverage application to the brake mechanism. My variable leverage brake mechanism also provides for the power to be increasingly ap-' plied through the operative movement necessary to set the brakes of the vehicle without any-tor mination or fade-out of the increasingly ap plied leverage application throughout the operation of setting the brakes of the vehicle.

It is also to be understood that my variable leverage brake mechanism will notlbe limited-to an application in which the driver manually exerts operative pressure for operating the brakes of the vehicle, nor to brake mechanisms, but can be applied and installed with various mechanisms where it is desired to apply and increase the applied pressure with a greater leverage through the movement of the control lever member having a limited amount of operating movement. I claim:

1. In a variable leverage mechanism for oper-' "brake: mailman a; vehicle "provided mechanism'havingfa brake 7 a1 control lever,'the'combination of a member anhe-red o aportionoi the vehiclameans for adposition of said member, a I W connectedto each other and tosaid ember, cond pair'oilinkspivotally tofeach other,andltoone of the ends aid first mentioned pair of, links, a pivotally connected'to said first ned and said. second pair of links at the where said first mentioned and said second i; arepivotally connected together, to operativelyfconnecting the brake convehi'cle with said second pair of H I int whem said pair, of links are pivotally con ected together, said lastmentioned means extending between, saidthird pair, of links, aljbracket member. pivotally connected to said thirdpair o f links; and means for adjustably connecting said third pair of links to the brake operating, mechanism, of; the vehicle.

2. In a variable leverage mechanism for operating the brake mechanism of a vehicle provided with power developing means, the combination of a toggle mechanism comprising a pair of links pivotally connected together, said pair of links being anchored, at the point where they are connected together, against longitudinal movement, said toggle mechanism further comprising a second pair of links connected together and with said first mentioned pair of links, a third pair of links each connected with one of, said first mentioned and said second pair of links, said third pair of links extending substantially parallel when the brake mechanism is not being operated, a member connecting the remaining ends of said third pair of links, said third pair of links together with said last mentioned member operatively connecting said toggle mechanism with the brake mechanism of the vehicle, and a rod member connected with said second pair of links and with the power developing means .of the vehicle, said rod member having its point of connection with said second pair of links at a point intermediate the anchored end of said toggle mechanism and the outer ends of said third pair of links.

3. In a variable leverage mechanism having a brake lever for operating a vehicle, the combination of an anchor-ed member, a toggle mechanism comprising four link members, two of said link members being connected at their forward ends to said anchored member, the other two of said link members of said toggle mechanism having their ends adapted for movement towards said anchored member, means for operatively connecting said last mentioned ends of said two link members with the brake lever of the vehicle, and means for operatively connecting the outer-most ends of said four link members with the brake mechanism of the vehicle.

4. In a variable leverage mechanism for operating a brake rod operatively connected with the brake mechanism of a vehicle, said brake mechanism being provided with a brake control lever, the combination of a member anchored against movement, two pairs of toggle members connected with each other, one of said pairs of toggle members being connected to said member, link members operatively connected with each of said pairs of toggle members and with said brake rod of the brake mechanism of the vehicle, and a rod member pivotally connected with one of said pairs of toggle members and with the brake control lever of the vehicle.

atinga brake mechanismhaving a brake control lever, the combination of an-anchored member, a pair of links each having ends pivotallymounted and connected with said anchored memberto anchor said pair of links against longitudinal movement, a secondpairof links each pivotally connected withone orsaia first mentioned pair of links and adapted for longitudinal movement,a

rod, means operatively connecting an end of each longitudinally adjacent the outer sides of said first mentioned means.

6.- In a variable leverage mechanism for operating a brake mechanism, of a vehicle having a brakecontrollever, the combination of a rod member operatively connected with the brake mechanism and adapted to transmit operating forces thereto, a pair of link members operatively connected with said rod member, a plurality of pairs of links pivotally connected with each other and with said first mentioned pair of link members, a bracket member pivotally connected with and anchoring one of said plurality of pairs of links against longitudinal movement, and rod means for operatively connecting one of said plurality of pairs of links with the brake control lever, said last mentioned means extending between said first mentioned pair of link members.

'7. In a variable leverage mechanism for operating a brake mechanism, the combination of an anchor bracket, four links pivotally connected with one another, two of said four links being pivotally connected with said anchor bracket to hold said two links against longitudinal movement, rod means for applying pressure to two of said links to move the outer ends of said four links outwardly relative to the anchored portion of said first mentioned two of said four links, a pair of links pivotally connected with and adapted to move with the outer ends of said four links, and bracket means for connecting said last mentioned pair of links with the brake mechanism.

8. In a variable leverage mechanism for operating a brake mechanism of a vehicle having a brake control lever, the combination of a member suitably anchored to a portion of a vehicle, a pair of links pivotally mounted on said member, a second pair of links pivotally connected to each other and to the outer ends of said first mentioned pair of links, means for applying pressure to the inner ends of said last mentioned pair of links, said means being operatively connected with the brake control lever of the vehicle, a pair of link means pivotally connected with the outer ends of each of said first mentioned and said second pairs of links, and bracket means pivotally connected with said last mentioned pair of link means and operatively connecting said last mentioned pair of link means with the brake mechanism of the vehicle.

9. In a variable leverage mechanism for a vehicle provided with brake operating means having a brake control lever, the combination of a bracket member anchored on the vehicle, a pair of links pivotally connected to said bracket member, a second pair of links pivotally connected to each other and tosaid first mentioned pair of links, a pair of link means pivotally connected to said first mentioned and sa d ec P of links at T earn fa variable leverage mechanism for oper i points where said first mentioned and said second pair of links are pivotally connected together, rod means pivotally connected with second pair of links at a point where said second pair of links are-pivotallvconnected together, said rod means being operatitely connected with the brake control lever of the vehicle, a second bracket member pivotally connected to each of said pair of link means, and means for connecting said second bracket member to the brake operating mechanism of the vehicle.

10. In a, variable leverage mechanism for operating the brake mechanism of a vehicle having a brake control lever, the combination of an anchorage member, a pair of links pivotally supported on said anchorage member, a second pair of links pivotally connected together and to said first mentioned links, a pair of pull means each pivotallyconnected to one only of each of said first mentioned and said second pairs of links, a second bracket connecting the other ends of each ing operatively connected with the brake operating pair of links and the brake control lever of the vehicle.

11. In a vehicle, a variable leverage mecha-,

nism for operating a brake mechanism provided with power developing means, the combination of a toggle mechanism comprising four links pivotally connected solely at their end' portions and arranged substantially in a rectangular formation when the brake mechanism is not being operated, means anchoring one corner of the rectangular formation against longitudinal movement relative to the variable lever mechanism, means connecting the opposite comer of the rectangular formation with the power developing means, the side and said opposite corner of the rectangular formation being adapted to move longitudinally relative to the variable lever mechanism, and means further connecting the rectangular formation with the brake mechanism of the vehicle.

AUGUST E. WIISHUSEN. 

